Selection of oil & gas drilling core Technology is very important to scientifically and reasonably lay down scientific-technical development strategy in oil & gas drilling.

An approach to applying of side-tracking horizontal well in thin heavy oil reservoirs with bottom water;

Recover low permeability high pour-point oil reservoir inblock Jing17 by side-tracking horizontal well and lateral well;

For the reason that its well-bore has larger curvature,smaller annular space between drilling string and borehole,the inner casing re-entry horizontal well requires not only build-up rate higher but also annular space large as possible,so as to improve drilling fluid's cuttings-carrying capacity.

Aiming at the hydrodynamics characteristics,in this paper,a research on slim hole fluid mechanics in re-entry horizontal well was finished by adopting eccentricity annulus axial & screw flow theory.

Static and strength analysis of perforated string in side tracking horizontal well;

Top screen pipe cementing technology of casing and liner in horizontal well and sidetracking horizontal well;

Compound plugging removal technology and its application in sidetracking horizontal well;